building and road construction, water and wastewater generosity peaks in the double-walled spiral pipe fasteners

摘要

PURPOSE: A coupling for a poly ethylene(PE) double wall spiral tube is provided to delivery the PE spiral tube in disassembly state and assembly the tubes along a water tube and inject mortar into an inlet of the PE tube. CONSTITUTION: A coupling for a poly ethylene double wall spiral tube(1) includes an inner surface and an outer surface. An inner space is formed between the inner surface and the outer surface. The outer surface bends along a spiral direction in a certain interval. The inner space is formed to engage the depressions(2) with and a junction(4). The inner space is filled with mortar. The depression is formed with an assembly hole to be engaged with a bolt(10) fastening a nut at the junction.